Group Therapy for Teen Anxiety and Depression Shows Promise in Spanish Public Mental Health Center

Anxiety and depression are among the most common psychological struggles of adolescence, and they rarely arrive alone. A teenager who develops panic attacks may slide into low mood; a depressed adolescent often carries intense worry beneath the surface. For decades, clinicians have treated these conditions as separate diagnostic categories, each with its own treatment manual. A new study from Spain challenges that fragmentation, reporting that a single group-based therapy targeting the shared emotional machinery behind anxiety and depression can be delivered successfully to adolescents in a public outpatient mental health center. The research, published in BMC Psychology, offers one of the first real-world tests of a group adaptation of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in Adolescents, known as UP-A, in routine clinical care.

The UP-A is built on a deceptively simple premise: anxiety and depressive disorders share common underlying mechanisms, most notably difficulties in regulating intense emotions and a tendency to avoid or escape uncomfortable emotional experiences. Rather than teaching teenagers separate skills for panic, social anxiety, generalized worry, or depression, the protocol trains them to notice, tolerate, and respond flexibly to whatever emotion they are feeling. Its theoretical foundation draws on emotion science and cognitive-behavioral principles, emphasizing that emotional disorders persist when people fight their feelings rather than working with them. In adolescents, whose emotional systems are still developing and whose symptoms frequently shift between diagnostic categories over time, this transdiagnostic logic has particular appeal.

The Spanish research team, led by Lucía Cortés and Julia García-Escalera of the National University of Distance Education (UNED) together with clinicians from Majadahonda’s Mental Health Center in Madrid, set out to answer a practical question: could this protocol, which had shown promise in individual sessions, work in a group format inside a public mental health service? Group delivery matters enormously for cash-strapped public systems. One therapist can treat several adolescents simultaneously, waiting lists shrink, and the group itself becomes a therapeutic tool, allowing teenagers to see that peers share their struggles and to practice new emotional skills in front of an audience that understands.

The study enrolled thirty-one adolescents with a mean age of 14.03 years, 87.1 percent of whom were female, in a sixteen-session group intervention. The design included three additional group sessions for parents, reflecting growing evidence that treating an adolescent in isolation ignores the family system in which emotional problems unfold. Parents learned the same core ideas about emotions and avoidance, so they could respond to their child’s distress in ways that supported rather than undermined the skills being practiced in therapy. The intervention was delivered by clinicians within the center itself, not by researchers in a laboratory setting, which is precisely what makes the preliminary evaluation notable: it tested feasibility under the messy, realistic conditions of routine public care.

The results were encouraging on every dimension the team measured. Just over eighty percent of participants, 80.65 percent, completed the full treatment, a completion rate that compares favorably with many adolescent interventions, where dropout is a persistent challenge. Adolescents and parents alike reported high satisfaction with the program and strong therapeutic alliance, the sense of trust and collaboration between client and therapist that research consistently links to better outcomes. In a group format, alliance extends beyond the therapist to the group as a whole, and the strong ratings suggest the teenagers felt connected to both their clinicians and their peers.

The clinical findings were equally significant. Adolescents themselves reported meaningful improvements in emotional symptoms and in the emotion regulation strategies the protocol is designed to strengthen. Parents observed reductions in their children’s depressive symptoms. Independent clinician ratings, which provide a check on the self-report and parent-report data, indicated reduced diagnostic severity and improved day-to-day functioning. In other words, the teenagers were not just feeling better on questionnaires; the clinicians who assessed them saw the intensity of their diagnoses ease and their ability to handle school, family, and social life improve.

Technically, the study is a preliminary, uncontrolled evaluation rather than a randomized trial, and the authors are careful about what that means. Without a comparison group, improvements cannot be attributed with certainty to the treatment itself; some change might reflect natural remission, regression to the mean, or the simple passage of time. The predominantly female sample also limits how far the findings generalize to boys. The study was retrospectively registered on ClinicalTrials.gov, and the team explicitly calls for randomized controlled studies to confirm the results. Yet the pattern of change across three independent sources of information, adolescent self-report, parent report, and clinician rating, is the kind of convergent evidence that preliminary evaluations are designed to detect, and it justifies the investment that a full randomized trial would require.

The broader significance of the work lies in its setting. Public mental health systems across Europe and beyond face rising demand for adolescent care, chronic underfunding, and long waiting lists, while most evidence-based treatments were developed and tested in university clinics with carefully selected samples. Demonstrating that a transdiagnostic protocol can be adapted to groups and delivered by regular clinicians in a Spanish public center addresses the critical gap between research and practice. If the findings hold up in randomized trials, the group UP-A could offer public services a way to treat a wide range of emotional disorders with a single, efficient, evidence-based program, rather than maintaining separate treatment pathways for each diagnosis.

There is also a scientific story here about how the field understands adolescent emotional disorders. Symptoms of anxiety and depression co-occur so frequently in adolescence that many researchers now view them as expressions of a shared vulnerability in emotional processing rather than as distinct illnesses. The UP-A operationalizes that view, targeting the mechanisms, emotional avoidance and dysregulation, that keep disorders alive regardless of their surface presentation. A group format adds a social dimension to this mechanism-focused approach: teenagers practice accepting and tolerating difficult emotions in front of peers who are doing the same work, which may itself counteract the shame and isolation that fuel avoidance.

The Spanish team’s next steps will determine whether this promising start becomes a standard tool of public adolescent mental health care. Randomized controlled trials with comparison groups, larger and more diverse samples, and longer follow-up periods are needed to establish whether the improvements persist and whether the group format matches the effectiveness of individual delivery. For now, the study stands as a concrete demonstration that a mechanism-based, transdiagnostic therapy can survive the journey from the research manual to the group room of a public mental health center, and that the adolescents who walked into that room, most of them struggling with the tangled combination of anxiety and depression that defines modern adolescence, left it measurably better equipped to face their emotions rather than flee from them.

Subject of Research: Psychology

Article Title: Development and preliminary evaluation of a group adaptation of the unified protocol for transdiagnostic treatment of emotional disorders in adolescents (UP-A) in a Spanish public mental health center

Article References: Cortés, L., García-Escalera, J., Casanova, I., Segura, A., Valiente, R. M., & Chorot, P. (2026). Development and preliminary evaluation of a group adaptation of the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders in adolescents (UP-A) in a Spanish public mental health center. BMC Psychology, 14(1), Article 1456. https://doi.org/10.1186/s40359-026-05472-8

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05472-8

Keywords: UP-A, transdiagnostic treatment, adolescent mental health, group therapy, anxiety, depression, emotion regulation, public mental health, BMC Psychology, Unified Protocol, Development, preliminary